Well. ....I am looking at the webbing"block"the oil circulation in design,the torque capacities in relation to prop rpm,500 to max.4000 rpm.the inherent torque/thrust conversions via stress on transfer thru engine core.If I were interested in a hi rpm hi hp motor I would go aluminum block.The702ci weighs wet stock at 1400 lbs.so far with calculated modifications the assembly would weigh out at 817 lbs.Via my wing area/torque/weight conversions this motor has a strong thrust "output"that if built right would make a very nice prop bender.Histories of a dog motor in the 60's is 60's concept.This is 2007,we've come a long ways.I look at the 16v merlin/packard rolls royce from the 1930's;the concept was similar to the model i'm thinking with new technologies via ceramic liners ceramic alloy pistons integrated magneto output controls via altitude density sensor controls. ......
I know I've a long ways to go;but what a challenge.
So do you think it's still crazy or just expensive?